This invention generally relates to knee braces of the type having hinged support members and more particularly, the present invention pertains to unilateral knee braces.
The present invention is directed to braces which protect the wearer from tearing or other stressing of ligaments or cartilage on the medial or inside portion of the knee joint, as a result of a blow from the lateral side of the knee. Generally, forces applied to the outside of the knee joint tend to cause the knee joint to bend about the lateral portion, so as to open or separate the medial portion of the knee. This tensions a system of ligaments and cartilage spanning medial portions of the knee joint, which attempts to hold that region of the knee joint in a closed condition.
Generally, athletes involved in contact sports are exposed to greater potentially damaging forces than other individuals, and therefore require greater support if their knee joint is to be protected against medial separation. However, these individuals also need a brace that is lightweight and provides a full range of motion.
One example of a unilateral lightweight knee brace is given in U.S. Pat. No. 3,528,412, issued Sep. 15, 1970 to Robert F. McDavid. The term "unilateral" is used herein to refer to a brace having a hinged support on only one side of a wearer's knee. In that patent, a knee brace is described having pivotally connected upper and lower portions adapted for securement to the upper and lower leg portions of a user. Stop means limit pivotal movement between the upper and lower portions. The arrangement uses straps for securing the brace to the leg and a resilient covering for the brace to prevent medial and lateral separation or other displacement of the knee joint. Despite the generally fine performance of this brace, athletes and others who are subjected to greater contact forces are constantly searching for braces which offer increased support of the knee joint.
Another example of a unilateral lightweight brace is that manufactured by Scott Grey of Colorado which has upper and lower leg-wrapping cuffs located above and below the knee joint. A rigid two-piece hinged support extends between the cuffs on the outside or lateral portion of a wearer's leg. An X-shaped elastic strap assembly, located on the opposing inside or medial portion of the wearer's leg also extends between the cuffs, and is directly attached at either end of the hinged support to assist in holding the brace on the wearer's leg and at the knee joint as the leg is flexed and bent at the knee.
Some contact sports require improved support, without an increase in weight or bulk of the brace construction. Heavier and more bulky conventional alternatives to the above braces usually include two sets of hinged supports, one on each side of the knee. These bilateral braces can offer some improved resistance to distortion of the knee in lateral directions. However, such performance is achieved at the expense of additional bulk and weight, and a more complex assembly, which may impede athletic activity.
The present invention is also directed to lightweight knee braces of the type wherein a single hinge support contacts only the lateral or outside portion of a wearer's leg, as opposed to arrangements, such as that of U.S. Pat. No. 3,581,741 issued June 1, 1971 to Rosman, wherein U-shaped rigid cups engage three sides (posterior or anterior, as well as the lateral and medial sides) of a wearer's leg. Alternatively, the present invention utilizes leg-wrapping cuffs to secure the hinged support about a wearer's leg.